Game Mechanics: Player Armor Class (Long)

[Treats]

I'm not positive but it seems here on P99 there is a soft cap in place when there shouldn't be. I'll do my best to try explaining how it is supposed to work along with some of the values that are missing and need to be found.

First a post from Kavhok (Original dev that worked on core game mechanics):

Re: Feed back on soft cap

Kavhok
EQ Designer
Posts: 14

Your AC cap was lowered. That was absolutely and unequivocally a nerf. I didn't mean in any way to imply otherwise.

Let me give a more full explanation of what happened, though. Here's how the AC formula used to work before the patch immediately preceding PoP:

The AC from your items was added up, but the value used for it was hard capped based on your level. This was the same for all classes. Once you had 289 raw AC from items (or 385 as a cloth class, since they get less effect from item AC), that was it. More AC from items wouldn't do anything.

After this, it added your class bonuses (including the monk bonus, which is equivalent to your level + 5 in raw item AC), defense skill bonus, agility bonus, and the AC from spell buffs.

Total AC at this point was capped again, this time based on class. In the Kunark-era code, this was a hard cap, but sometime during Velious it was changed to a soft cap for melee classes only. The return was fairly small, though.


The pre-PoP patch did a few things:

- The cap on item AC was no longer used except at lower levels (twinking was a concern since that was before recommended level items were in heavy use).
- Shield AC was added to the class-based cap to give shields more viability
- Class AC caps were changed. Monks were lowered the most, but beastlords were lowered to the same level as druids (yes, they were nerfed too). Cleric and shaman caps were raised above druids. The caps generally followed the armor archetypes of plate/chain/leather/cloth.
- All classes were given returns on AC over the cap, not just melee classes. All casters and priests received the least, followed by the melee classes. Rogues got the same return as monks, as did berserkers when the class was added. Beastlords and rangers got slightly more, followed by bards, then knights, then warriors.

The overall goal was to make the average dps (including mitigation, avoidance, block/dodge/etc.) taken for melee classes to be approximately:
Warrior > Knight > Monk > Bard > Ranger = Beastlord = Rogue

Aggregate data from live servers at the time was taken to determine median-AC stats for each class. Parses were run against NPCs 3-4 levels lower, facing front. The characters had cleric AC and shaman agility buffs and faced the NPC. The results of the parse were consistent with statistical analysis of the formulas in code:

Class War Pal Mnk
Level 51 51 51
Raw Item AC 184 181 107
Agility 157 144 169
Dodge 3.4% 3.1% 4.4%
Block 0 % 0% 10.2%
Riposte 4.4% 3.9% 4.1%
Parry 5.2% 4.6% 0%
Skill Evasion 12.9% 11.5% 18.7%
Hit Rate 61.2% 61.3% 58.2%
Avg Hit 72.6 72.9 74.6
% Hits for Max 10.2% 10.5% 11.5%
Avg Dmg / Round 59.7 61.1 54.5
DPS 28.2 28.8 25.7


Class War Pal Mnk
Level 60 60 60
Raw Item AC 296 281 163
Agility 177 152 187
Dodge 4.3% 3.9% 4.9%
Block 0 % 0% 11.4%
Riposte 4.8% 4.3% 4.5%
Parry 5.8% 5.2% 0%
Skill Evasion 14.9% 13.4% 20.8%
Hit Rate 59.4% 59.7% 59.3%
Avg Hit 107.3 109.9 113.6
% Hits for Max 10.4% 11.7% 13.6%
Avg Dmg / Round 87.4 91.7 86.1
DPS 50.8 53.3 50


The problem was that the average plate-equipped warriors and knights had barely any lead on monks in mitigation, due to the monk bonus, but the monk still had the lead in evasion. Contrary to popular belief, this is what prompted the nerf to monk mitigation, NOT high-end monks being rampage tanks.

The changes had little effect on average level 51 warriors and knights, but since the average level 51 monk was over the new nerfed AC cap, it increased their average damage taken per hit and increased the percent chance of max hits (in the above example) to 13%. Monks who had better than this median AC were hit harder by the nerf since it lowered their effective AC even more. Level 60 monks with exceptionally high item AC (Ssra+) weren't hit quite as hard because the uncapping of item AC gave them more returns on AC over the class cap. The median level 60 changes looked like this (evasion, of course, remained the same):

Class War Pal Mnk
Avg Hit 106 108.9 121.3
% Hits for Max 9.8% 11.2% 18.4%
Avg Dmg 86.4 90.9 91.9
DPS 50.2 52.8 53.4


Several months into PoP, the nerf was partially repealed and the monk AC cap was raised to the same level as druids and beastlords. Their return on AC over the cap was left at the same level. The reasoning at the time was based on a number of factors: the percentage of hits for max made taking damage even more unpredictable and raised the likelihood of one-round deaths more than we wanted, median AC increased for nearly all levels 51+ due to the new armor in PoP and trickle-down of old armor into the economy, and other issues were brought up.


Addendum:

Why were monks below 1160 AC affected?

The AC number you see is a composite of mitigation and avoidance. Defense skill increases both mitigation and avoidance, so gaining skill levels 50+ makes both numbers go up. At level 51, before the mitigation changes, a monk with no buffs, 150 agi, and 163 raw item AC was at the original AC cap with a displayed AC of 985. The nerf made it so that same monk with 118 AC, or 914 displayed, was now at the soft cap. Any level 51 monk with more than that would've experienced the nerf to varying degrees.

http://www.therunes.net/forums/viewt...hp?f=15&t=7706

The correct calculation for Total AC in Velious (pre soft cap) was:

Raw AC (Hardcapped based on level) + Class Bonus + Defense Skill Bonus + Agility Bonus + Spell AC = Total Displayed AC (Hardcapped again based on Class)

RAW AC

Hardcap on Raw AC for non casters was 289 at level 60. Hardcap for casters was 385. Looking at the numbers at the bottom of Kavhok's post, a level 51 Monk with 163 Raw AC was at the Hardcap. Raw AC caps for every class (except Nec/Wiz/Mag/Ench) per level should look like this from 51-60. It's just an assumption but I bet AC was hardcapped per level from 1-50 also. However the increase was much smaller. It looks like 3 AC per level.

Melee (non casters)

60 - 289
59 - 275
58 - 261
57 - 247
56 - 233
55 - 219
54 - 205
53 - 191
52 - 177
51 - 163
50 - 149 or 50 - 160
40 - 119 or 40 - 130
30 - 89 or 30 - 100
20 - 59 or 20 - 70
10 - 29 or 10 - 40
1 - 2 or 1 - 10

Caster (Nec/Wiz/Mag/Ench)

60 - 385
59 - 366
58 - 348
57 - 329
56 - 310
55 - 292
54 - 273
53 - 254
52 - 236
51 - 217
50 - 198
40 - 158
30 - 118
20 - 78
10 - 38
1 - 2

CLASS AC BONUS FROM RAW AC

It seems everyone EXCEPT casters used a 4/3 calculation for Class AC bonus. It's in the table below. There is a lot of information for AC on cached pages from Magelo from the boards there when they were trying to figure out the calculations. Found a few places saying at Level 75 an Iksar added 42 AC. Looks like the formula for this may have been (Level / 2) + 5. Raw Class AC bonus and Monk Bonus is added to Mitigation. Iksar bonus is added to Avoidance.

Class

Warrior - (Raw AC * 4) / 3
Paladin - (Raw AC * 4) / 3
Shadow Knight - (Raw AC * 4) / 3
Bard - (Raw AC * 4) / 3
Cleric - (Raw AC * 4) / 3
Shaman - (Raw AC * 4) / 3
Rogue - (Raw AC * 4) / 3
Ranger - (Raw AC * 4) / 3
Druid - (Raw AC * 4) / 3
Monk - (Raw AC * 4) / 3 + Monk Bonus ((Level + 5) * 4) / 3
Enchanter - (Raw AC + 1)
Wizard - (Raw AC + 1)
Necromancer - (Raw AC + 1)
Magician - (Raw AC + 1)

Race

Iksar - (Level / 2) + 5 added to Avoidance

DEFENSE SKILL BONUS

http://members.cox.net/sherrick/eqnumbers.htm

Avoidance = (T from table) + (Defense * 16/9), but never less than 0
Caster Mitigation = (Buffs/3) + (Defense/2) + (Equipment + 1)
Melee Mitigation = (Buffs/4) + (Defense/3) + (Equipment * 4/3)
Displayed AC = (Avoidance + Mitigation) * 1000 / 847

These look to be correct after more research. (T from table) refers to agility. All calculations are truncated. From the hard numbers at the bottom of Kavhok's post for a Monk this is what is known:

51 Monk
150 Agility
163 Raw AC
No Spell Buffs
985 AC (Original Hardcap)

Avoidance -- 52 + (233 * 16) / 9 = 466
Mitigation -- 0 + (233 / 3) + ((163 * 4) / 3) + ((51 + 5) * 4) / 3 = 368
Displayed AC -- (466 + 368) * 1000 / 847 = 984

AGILITY BONUS

See table here:

http://webcache.googleusercontent.co...&ct=clnk&gl=us

TOTAL AC HARDCAPS (Based on Class)

***Edit -- Showing Avoidance and Mitigation Hardcap separate instead of total. This is displayed AC using (Avoidance * 1000) / 847. These hardcaps on Avoidance are shown using 255 Agility. The only factors are Defense Skill, Agility and Iksar race.

Avoidance Hardcaps Class/Race

Level 60
255 Agility

Warrior - 602
Iksar Warrior - 643
Shadow Knight - 554
Iksar Shadow Knight - 596
Paladin - 554
Bard - 524
Cleric - 440
Shaman - 492
Iksar Shaman - 533
Rogue - 602
Ranger - 492
Druid - 492
Monk - 602
Iksar Monk - 643
Enchanter - 376
Wizard - 376
Necromancer - 376
Iksar Necromancer - 417
Magician - 376

Mitigation Hardcaps Class Only

Level 60
289 Raw AC (385 Raw AC for Casters)
Natureskin 20 AC
Shield of the Magi 32 AC (Used for Casters instead of Natureskin)
Bulwark of Faith 38 AC
Monk Bonus - ((Level +5) * 4) / 3

Warrior - 570
Shadow Knight - 560
Paladin - 560
Bard - 554
Cleric - 539
Shaman - 548
Rogue - 570
Ranger - 548
Druid - 548
Monk - 671
Enchanter - 567
Wizard - 567
Necromancer - 567
Magician - 567

Total Displayed Hardcap Class/Race

Warrior - 1172
Iksar Warrior - 1213
Shadow Knight - 1114
Iksar Shadow Knight - 1156
Paladin - 1114
Bard - 1078
Cleric - 979
Shaman - 1040
Iksar Shaman - 1081
Rogue - 1172
Ranger - 1040
Druid - 1040
Monk - 1273
Iksar Monk - 1314
Enchanter - 943
Wizard - 943
Necromancer - 943
Iksar Necromancer - 984
Magician - 943


TOTAL EFFECT OF AC ON MITIGATION AND AVOIDANCE

I read a post awhile back on The Steel Warrior that stated a warrior that added 100 AC received a 3-4% boost in avoidance and mitigation. This is irrelevant though because it was done in PoP or later.

1 AC = ? Avoidance
1 AC = ? Mitigation

Please post any post any worthwhile info you can find and I'll do my best to update this thread.

[greatdane]

I don't have anything of value to add, but it really surprises me just how insignificant of a difference there was between warrior and knight numbers. They're mostly less than 1% apart, confirming my belief that there really is no tangible advantage to a warrior tank (other than slightly higher HP) until defensive discipline comes into the picture.

[Martenus]

This is a feel Post i have no real Hard evidence to proof it but it seems AC has not the high impact it should be i have 1017 ac with my iksar monk on 55 and parsed like 30 mobs after that i took off my Ac gear for Ressit/Hp one just for another 30 mobs and there was nearly no diffrence with nearly 250 ac less got even less damge in resssit gear over those 30 mobs.

[Treats]

Originally Posted by greatdane [You must be logged in to view images. Log in or Register.]

I don't have anything of value to add, but it really surprises me just how insignificant of a difference there was between warrior and knight numbers. They're mostly less than 1% apart, confirming my belief that there really is no tangible advantage to a warrior tank (other than slightly higher HP) until defensive discipline comes into the picture.

Yep, there are really only a few things that factored into the AC equation that made a Warrior a better tank than a Hybrid. Pre-Kunark was even closer.

Warrior Defense Cap 252 and Class AC Bonus
Paladin/Shadowknight Defense Cap 230 and Class AC Bonus

Pre-Kunark:

Warrior Defense Cap 210
Paladin/Shadowknight Defense Cap 200

[Treats]

Added Class Bonuses from Raw AC
Added Iksar Race Bonus
Better Table for Agility
Figured Human/Iksar Monk Hardcap -- May not be correct

[Werlop]

So if this is accurate, monks should be even better? [You must be logged in to view images. Log in or Register.]

[Pudge]

wow - awesome post! great research

[Treats]

Originally Posted by Werlop [You must be logged in to view images. Log in or Register.]

So if this is accurate, monks should be even better? [You must be logged in to view images. Log in or Register.]

The numbers are very high for them. Keep in mind though that those caps were not even attainable for a Monk until high end Velious (ToV/Dain/Yelinak/Tormax/etc) with multiple pieces of all/all gear. The Warrior/Hybrids are still equipping Plate and the Monk is still equipping Leather with an added factor of weight (Monk goes over - loses AC) in Kunark.

Comparison in Raw AC from Best in Slot gear in Kunark era:

Warrior - 291 Raw AC
Monk - 135 Raw AC

[Treats]

Added the numbers on Raw AC for Casters (Nec/Wiz/Mag/Ench). Used Raw AC Level Cap from other classes.

(Raw AC * 4) / 3

60 - (289 * 4) / 3 = 385
59 - (275 * 4) / 3 = 366
And so on

[Furniture]

Does anyone have a working link of the tables posted in this thread? They dont work anymore